GNSS vs GPS: What Are the Differences?

Navigation technology has come a long way over the years, and today it’s available on our mobile phones and devices – which certainly makes getting from A to B a lot easier. But, beyond helping you plan your road trip, the technology plays a central role in supporting the operations of a myriad of industries, such as agriculture, aviation, the military and more. 

Satellite navigation refers to a system of satellites that provide geospatial positioning and transmit longitude, latitude and elevation – helping us determine locations and plot our routes. 

This information is all transmitted from satellites and GNSS survey equipment taps into these satellite systems. GPS equipment, meanwhile, taps into a select few and is an example of a GNSS. 

So, while GPS and GNSS are both systems that receive information from satellites and can (fairly) accurately pinpoint a location on the map, GPS is actually just one of several GNSS systems. 

GPS was one of the first GNSS technologies to become available to the layperson, which is why it’s more recognisable as a term. The two are often used interchangeably, but there are a number of important differences. We’ll discuss these below as well as offer up some tips for deciding which of the two technologies is right for you and your project.

What is GNSS Technology?

As briefly outlined above, GNSS – which stands for Global Navigation Satellite System – refers to any and all global satellite positioning systems, including GPS. It originally came into existence to assist in military developments, but is now accessible to everyone.

GPS is the U.S. global positioning system, but GPS isn’t the only GNSS, there are a number of other satellite navigation systems. These include:

  • The European Union’s Galileo 
  • India’s IRNSS 
  • Japan’s QZSS 
  • China’s Beidou 
  • Russia’s Glonass

When you use GNSS technology, you have access to all of the satellite navigation systems. 

This means it can provide detailed positioning across the globe and, if one satellite is impaired, it can switch to receiving information from another.

What are the advantages and disadvantages of using GNSS technology?

While GNSS offers access to numerous satellites and can provide accurate positioning data, it does come with some drawbacks. Below we discuss the main pros and cons of the technology.


  • GNSS provides access to all global navigation systems, meaning it can be used globally and in more remote areas. 
  • GNSS is much faster than traditional surveying methods, and is ideal for mapping larger areas, where centimetre-level accuracy is sufficient. 
  • Can provide accurate timing and location – accuracy is typically within 1 metre (though many Trimble GNSS solutions can measure within millimetre accuracy). 
  • Increased accuracy and high performance can help prevent errors, thus saving time and money – this is particularly crucial in land surveying, civil engineering and rail. 
  • In surveying, unique GNSS products such as the Trimble R12i, can provide connectivity even in obscured locations such as a dense forest. 
  • GNSS receivers automatically filter out information from failed satellites.


  • Signals can be blocked by buildings, trees in some locations. 
  • Can be prone to spoofing or jamming, which is when a false signal is received from a GNSS simulator, leading to inaccurate data.

What are the main applications of GNSS technology?

GNSS is used in a variety of industries, including:

  • Mapping 
  • Surveying
  • Farming
  • Navy
  • Aviation

What is GPS Technology?

GPS – an acronym for Global Positioning System – is an example of GNSS and originates in the United States. It comprises 31 Earth orbit satellites across six orbital planes. The exact number of satellites is changeable as some expire and, occasionally, new ones are added. 

It’s existed since 1978 as a tool for the U.S Department of Defence, and only became available to civilians in 1994. It’s currently the world’s most used GNSS, but only provides positioning informed by US satellites. 

What are the advantages and disadvantages of using GPS technology?

Again, GPS does have some weaknesses as well as some benefits, which we delve into below:


  • The GPS system is automatically calibrated. 
  • GPS provides people with real-time location which is useful for mapping and geocaching.


  • The accuracy of GPS is reliant on signal quality which varies according to atmospheric events, including electromagnetic interference – this can result in errors and drive down accuracy significantly. 
  • GPS depends on the reception of radio satellite signals – if these are interrupted or if satellites fail, it can quickly become unreliable. 
  • As GPS is controlled by one organisation, limitations could be placed on the signal without warning.

What are the main applications of GPS technology?

GPS is employed for a number of activities, both professional and recreational, including:

  • Mapping 
  • Locating positions
  • Social activities
  • Travelling
  • Road transportation
  • Telecommunications

What Are the Differences Between GNSS and GPS?

The essential difference between GNSS and GPS is that the former refers to all satellite navigation systems, while GPS refers only to the American offering of the technology. 

However, they also have the following differences when used in practice:


GNSS and GPS are certainly not equal in terms of their coverage. GPS only covers specific areas of the globe, while the wider GNSS system covers over two-thirds of the world, including remote and obscure locations.

Notable, as GPS only receives signals from US satellites, it fails to cover a number of areas. Additionally, mountains and skyscrapers can actually block the satellites it does interact with. 

GNSS, however, employs several satellite systems from a variety of countries making its coverage far superior. 


GPS receivers typically provide accuracy within 10 metres with survey grade GPS often achieving centimetre accuracy. GNSS receivers on the other hand, can typically provide accuracy within 1 metre, with some surveying products offering millimetre accuracy, such as the Trimble R780. This is because GNSS systems use multiple satellite constellations to determine location. 

So as to the question ‘which is more accurate: GNSS or GPS?’ The answer is clear: GNSS. However both can experience decreased accuracy due to bad weather conditions and electromagnetic interference. 


At the time of writing, GPS uses 31 satellites and GNSS systems use a total of 35. This effectively means GNSS systems can offer more accurate information simply because they have access to more satellites within their constellation. 

While in urban dwellings this doesn’t make a huge difference, in more remote locations, GPS coverage tends to be significantly weaker than GNSS.


Both GPS and GNSS systems are widely used in surveying, but GNSS constellations can provide more accuracy than GPS alone.

Note here that, while accuracy and precision both measure observational error, accuracy refers specifically to how close a measurement is to the true value. Precision, meanwhile, is how close different measurements of the same reading are to each other. 

So, with GNSS, its accuracy refers to how closely it determines your location to be vs where you actually are. Precision, on the other hand, is how often it determines your location to be accurate. 

GNSS vs GPS: Which One Should You Choose? 

Choosing whether to opt for a GNSS system or GPS depends on how you intend to use the technology. If surveying is your goal, you may prefer to opt for GNSS given its superior accuracy. 

However, if you are simply a hobbyist or wish to use location positioning for recreational activities such as geocaching, GPS will likely meet all of your needs while still providing sufficient accuracy. 

GPS is also widely available and fairly reliable. However, it is reliant on clear signals and can be affected by signal jamming and interference. 

GNSS doesn’t tend to suffer from this as badly as it taps into multiple satellite systems. Therefore, if one becomes unavailable, it can still access satellite navigation from a different system. 

All GPS is GNSS, But Not All GNSS is GPS

GNSS and GPS are both satellite navigation technologies that provide positioning information. GPS is the more well known term and is typically widely available as it’s used in a wider range of navigation products. GNSS, however, due to the fact it utilises all satellites across different countries, provides more robust coverage and a greater degree of accuracy. 

When it comes to deciding which mapping technology is right for your project, the standard advice is that if you require superior accuracy and reliability, GNSS is the better system to opt for. 

However, both technologies are always evolving, with new advancements and innovations occurring on a frequent basis. So it may well be that GPS’ accuracy rivals GNSS before long, or that GNSS becomes more affordable for the layperson. 

At KOREC Group, we specialise in providing mapping systems and equipment for the geospatial, engineering and construction sectors in the UK and Ireland, and it’s our mission to make your work as efficient as possible. 

We supply a number of GNSS mapping products at various price points to suit your needs, we also offer a fully supported survey equipment hire service, just get in touch to find out more.